Toward generic image dewatermarking?

During the last decade, a significant effort has been put into designing watermarking algorithms. The watermarking community now needs some advanced attacks and fair benchmarks in order to compare the performances of different watermarking technologies. Moreover, attacks permit the weaknesses of an algorithm to be found and consequently trigger further research in order to overcome the problem. These ideas motivated the creation of the European Certimark project. After a short definition of dewatermarking, we present an original attack based on self similarities. This attack is then put to the test with three different publicly available watermarking tools. Finally, we discuss briefly the feasibility of a generic attack i.e. a dewatermarking attack which should succeed in removing whatever watermarks have been inserted by whatever watermarking tools.